I have owned and used an enormous variety of supplemental items over several decades. They nearly all did something good, but very few have stood the test of time in that their cost and additional demands on my attention have usually failed to add any real overall improvement to my complete, all-inclusive handloading/shooting process. The two go together as one, what demands get made on one affect the overall whole.
First, my Dillon RL-550B press is indispensable, with additional powder measures, toolheads, and a second primer feed setup. A good drop tube, an RCBS collet bullet puller setup, and a Dillon strong mount and bullet tray round out the rest of the indispensables. ** Edited to add my Dillon Super Swage, as well as an inside case neck chamfer tool for when I'm reloading boxer primed steel cartridge cases. I do believe that concentricity has great value in a custom tight necked chamber, but none of mine are so configured.**. I now use RCBS Water Soluble case lube, and I haven't had a stuck case in the decade and a half since I started using it. I still use the original Lee mechanical dial caliper that came with the (used) Dillon back in the mid-90's and the RCBS digital scale I acquired around the millennium may be a tad slow, but even so, I weigh every charge that counts (and that's every one of them).
Weighing every charge may seem like a chore, but once I dropped playing with all the other optional bells and whistles, the entire process became a lot more efficient, and if there's an accuracy downside, it's certainly small enough to embrace with a smile. Weighed charges are worth the extra effort, no matter what it is. This is where the progressive press earns its kudos. I don't keep track of rounds per hour production rates or overall times for anything else associated with handloading. It takes as long as it takes, and that's good enough for me.
I have no secret-squirrel handloading secrets. KISS is a very good mantra for me. I once thought I had a mindblowingly simple process for managing neck tension, but as of now, that's off the menu. Just make the ammo simply and with truly diligent attention to each step, and you come out ahead in the long run (unless, of course, you get hung up on 'that perfection thing'). Nobody makes perfect ammo, and those of us who don't try attaining the impossible get to make and shoot a lot more of it.
Good ammo is ammo that hits the target, period. If you can't, stop blaming the ammo and consider questioning your judgment regarding distances and hit probabilities. Every marksmanship system has its own unique capabilities, and that includes the capability of missing when we ask too much of it.
Even cheaper factory ammo is great ammo when we use it within its reasonable capabilities. The failures don't reside with the ammo, they reside with the unrealistic expectations. Nobody would call Russian Spamcan X54R surplus stuff precision ammo, but it still did a pretty good job of driving the Germans all the way back to Berlin back in 1945.
Greg